@Mentor-Gashi
Now - it seems - these '.../targets/ramips/mt7688/packages' and '.../onion' are unnecessary lines in the /etc/opkg/distfeeds.conf file.
BTW @Lazar-Demin has a bon mot: "It worked at previously!"

Please notice it: the most fresh working official firmware of Omega2(+) v0.1.10-b160 is nine (9) months old (release date 01-Mar-2017).